Recording results: tables, units and the solidusSpec S2
In short
A Cambridge results table is ruled, with the independent variable in the first column and each heading giving the quantity and unit separated by a solidus, such as time / s. Units go only in the heading, never in the body. Record data to the precision of the instrument, to the same decimal places in each column.
Paper 6 often gives marks just for drawing a correct results table. Cambridge has strict rules for this, and the most important one is the solidus: the quantity and its unit are separated by a slash, as in time / s.
The rules for a results table
- Draw a ruled table with a border and lines between columns.
- Put the independent variable in the first column and the dependent variable (with any repeats and the mean) in the next columns.
- Head each column with the quantity and the unit, separated by a solidus: temperature / °C, time / s, mass / g, volume / cm³.
- Do not put units in the body of the table, only in the heading.
- Record data to reflect the precision of the measuring instrument, and give every value in a column to the same number of decimal places.
- For tests with no number, record the observation itself, for example 'blue-black' or 'stays orange-brown', not just 'positive'.
| Feature | Badly drawn | Well drawn |
|---|---|---|
| Column heading | Time (s) or Time or Seconds | time / s |
| Heading for a calculated value | Change | change in mass / g |
| Data in the body | 45 s | 45 |
| Decimal places in one column | 2.5, 2.48, 2.6 | 2.50, 2.48, 2.60 |
| Qualitative result | positive | brick-red precipitate |
| concentration of sucrose / mol dm⁻³ | mass at start / g | mass at end / g | percentage change in mass / % |
|---|---|---|---|
| 0.0 | 2.50 | 2.75 | +10.0 |
| 0.2 | 2.48 | 2.60 | +4.8 |
| 0.4 | 2.52 | 2.40 | −4.8 |
| 0.6 | 2.50 | 2.30 | −8.0 |
Precision follows the instrument. A stop-clock reading to 1 s gives whole seconds. A thermometer with 1 °C graduations gives readings to the nearest 1 °C. A ruler marked in mm gives lengths to the nearest mm. A balance reading to 0.01 g gives masses such as 2.50 g, so write the final zero.
Processing results
Percentage change in mass
A potato piece has a mass of 2.50 g at the start. After 30 minutes in a sucrose solution its mass is 2.20 g. Calculate the percentage change in mass.
- change in mass = 2.20 − 2.50 = −0.30 g
- divide by the starting mass: −0.30 ÷ 2.50 = −0.12
- multiply by 100: −0.12 × 100 = −12
Answer: −12 % (the minus sign shows the mass decreased)
Always divide by the starting value, not the final value. Keep the + or − sign, because it shows whether the mass went up or down.
Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026